Testing methods for direct measurement of particle settling velocities and fluxes in the sea

沉积物捕集器被广泛用于量化物质的垂直通量，并收集沉降颗粒有机物（POM）进行化学分析。他们提供了POM通过水柱的空间、情景、季节和年际通量的证据，将地表水过程的变化与海洋内部和海底的通量联系起来，并表明强烈的矿化和蚀变会影响水柱中的POM。 在这个项目中，斯托尼布鲁克的纽约州立大学的研究人员将修改最近开发的沉降速度陷阱，作为MedFlux计划的一部分，通过在旋转球阀的上方和下方安装摄像机来监测颗粒落入陷阱和球旋转后的沉降速率。这些测量应该使他们能够明确地确定颗粒是否结合在球上产生人为的高沉降速度，或者如果以前的沉降速度估计是真正robust.Broader影响：测试和发展的沉降速度陷阱将理想地允许在现场测量颗粒沉降速率，反过来又提供了关键的限制元素循环内的水柱。收集的样品还将允许评估各种压载物材料的相对重要性（例如，碳酸盐、蛋白石等）。 虽然捕集器的开发对我们理解生物泵很重要，但更好地理解碳通量的能力也对海洋和大气中的二氧化碳浓度等更大的社会问题产生直接影响。

Sediment traps are widely used to quantify vertical fluxes of material and to collect sinking particulate organic matter (POM) for chemical analyses. They have provided proof of spatial, episodic, seasonal, and interannual fluxes of POM through the water column, have linked variability in surface water processes to fluxes in the interior of the ocean and to the sea floor, and have shown that intense remineralization and alteration affects POM in the water column. In this project, researchers at the State University of New York at Stony Brook will modify a settling velocity trap developed recently as part of the MedFlux Program by installing cameras above and below the rotating ball valve to monitor particle settling rates as they fall into the trap and after the ball rotation. These measurements should allow them to unequivocally determine whether particles are combining on the ball to produce artificially-high settling velocities, or if the previous settling velocity estimates are truly robust.Broader Impacts: Testing and development of the settling velocity traps will ideally allow for in situ measurements of particle settling rates that in turn provide critical constraints on elemental cycling within the water column. Collected samples will also allow assessment of the relative importance of various ballast materials (e.g., carbonate, opal, etc.). While the trap development is important to our understanding of the biological pump, the ability to better understand carbon fluxes also has a direct impact on larger societal issues such as CO2 concentrations in both the oceans and the atmosphere.